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Behind SEQopts()

SEQopts() provides the primary API to changing internal options of SEQuential(). While the documentation should go over their use, we will expand on them here in greater detail:

The options

General Options

Option Name Description Input Type Example
bootstrap Whether bootstrapping should take place Boolean TRUE
bootstrap.nboot Number of bootstraps to run in addition to the full model Integer 100L
bootstrap.sample Subsample of data to use when bootstrapping Float [0, 1] 0.8
calculate.var Whether to calculate the robust standard errors for the outcome model Boolean FALSE
compevent Column name for competing event variable Char “LTFU”
covariates If provided, forces covariates for outcome models Char “X1+X2*X3+X4”
data.return Whether to return expanded data as output Boolean TRUE
followup.class Whether to expand followup values to an indicator matrix Boolean FALSE
followup.include Whether to include ‘followup’ and ‘followup^2’ in outcome models Boolean TRUE
followup.max Maximum value of followup per trial Numeric 60
followup.min Minimum value of followup per trial Numeric 0
followup.spline Whether to format followup values to a spline Boolean FALSE
hazard Whether to estimate the hazard ratio Boolean FALSE
km.curves Whether to estimate kaplan meier survival curves and data Boolean TRUE
multinomial Whether to expect more than 2 treatment types Boolean FALSE
ncores Number of cores to use in parallel multisession Integer 8L
nthreads Number of threads to use for data.table manipulations Integer 16L
parallel Whether the bootstrapping should be run in parallel Boolean TRUE
seed Starting seed for random number generators Integer 1636
selection.first_trial Selects only the first eligible trial in the expanded dataset Boolean TRUE
selection.prob Subsample of total IDs to select Float [0, 1] 0.8
selection.random Whether to randomly select IDs with replacement to run analysis Boolean FALSE
subgroup Column name for subgroup analysis Char “sex”
survival.max Maximum value for Risk/Survival curves Numeric 60
treat.level Treatment levels to compare List list(0, 1)
trial.include Whether to include ‘trial’ and ‘trial^2’ in outcome models Boolean TRUE

Weighting Options

In general these only affect analytic methods of ‘dose-response’ and ‘censoring’. However, providing cense will allow ITT to be weighted in the case of a censoring variable like loss-to-followup.

Option Name Description Input Type Example
cense Column name for censoring variable Char “LTFU”
cense.denominator If provided, forces denominator covariates for censoring models Char “A1+A2*A3+A4”
cense.eligible Column name for indicator column defining which rows to use for censoring model Char “eligible_cense”
cense.numerator If provided, forces numerator covariates for censoring models Char “Z1+Z2*Z3+Z4”
denominator If provided, forces denominator covariates for weight models Char “C1+C2*C3+B4”
numerator If provided, forces numerator covariates for weight models Char “B1+B2*B3+B4”
weight.eligible List of columns for eligibility in weight models with certain treatment values List list(‘we1’, we2’)
weight.eligible_cols List of column names for indicator columns defining which weights are eligible for weight models List list(“eligible1”, “eligible2”)
weight.lag_condition Whether weights should be conditioned on treatment lag value Boolean TRUE
weight.lower Lower truncation for weight values Float 0.0
weight.p99 Whether to truncate weights at the 99% percentile Boolean TRUE
weight.preexpansion Whether weighting should be done on pre-expanded data Boolean TRUE
weight.upper Upper truncation for weight values Float 1.0
weighted Whether the analysis should be weighted Boolean TRUE

Plot Options (km.curves = TRUE)

All of these can be changed after SEQuential has finished analysis - if you forget to add them, no need to stop and restart. Additionally, SEQuential will output the data used for the plot if you would like to customize it yourself through your preferred plotting software.

Option Name Description Input Type Example
plot.colors Figure colors for output plot List list(“red”, “blue”)
plot.labels Legend labels for output plot List list(“Tx 0”, “Tx 1”)
plot.subtitle Subtitle for plot output Char “My Plot Subtitle”
plot.title Title for plot output Char “My Plot Title”
plot.type Type of output plot (“survival”, “risk”, “inc”) Char “survival”

Special Cases

Option Name Description Input Type Example
deviation Create switch based on deviation from column Boolean TRUE
deviation.col Column name for deviation Char “deviation_var”
deviation.conditions RHS evaluations of the same length as treat.levels List list(“>3”, “==1”)
deviation.excused Whether deviations should be excused by deviation.excused_cols Boolean TRUE
deviation.excused_cols Excused columns for deviation switches List list(“excuse1”, “excuse2”)
excused When censoring, whether there is an excused condition Boolean TRUE
excused.cols List of column names for treatment switch excuses List list(“excuse1”, “excuse2”)

Internal Options

These are internal options that change output name of covariates or the decomposition method when estimating coefficients.

Option Name Description Input Type Example
fastglm.method Method for decomposition by fastglm Integer 3L
indicator.baseline Identifier for baseline variables Char “_bas”
indicator.squared Identifier for squared variables Char “_sq”